Graphite materials are mainly used as materials for negative electrodes of lithium-ion secondary batteries. On the other hand, non-graphite carbonaceous materials with higher capacities than the theoretical capacity of graphite materials have been reported, which means that such non-graphite carbonaceous materials have also been developed.
For example, Patent Literature 1 proposes improved activated carbon, which is one of the non-graphite carbonaceous materials, as a negative electrode material. This negative electrode material is produced by depositing a volatile organic component such as pitch on the surface of activated carbon. According to Patent Literature 1, deposition of such a volatile component allows control of pore distribution in activated carbon and thus the resulting negative electrode material is suitable for use in high-capacity and high-power batteries.